Benzothiazole, 2,3-dihydro-, 1,1-dioxide synthesis

Yield:4433-53-8 97%

Reaction Conditions:

with acetic acid;3-chloro-benzenecarboperoxoic acid at 30 - 35; for 60 h;Reagent/catalyst;Temperature;

Steps:

1; 2 Example one:

Add 2,3-dihydrobenzothiazole (II) (3.43g, 25mmol), m-chloroperoxybenzoic acid (17.2g, 0.1mol) and 150mL of acetic acid into the reaction flask, and stir at 30-35°C for 60 hours.The acetic acid was evaporated under reduced pressure, and the residue was neutralized with 50 mL of sodium thiosulfate solution. Extract three times with ethyl acetate, combine the organic phases,Wash with saturated sodium bicarbonate solution, saturated brine and water successively,Dry with anhydrous sodium sulfate. Concentrate under reduced pressure,The residue was recrystallized from n-hexane to obtain 4.1 g of off-white solid 2,3-dihydro-1,1-dioxo-benzothiazole (III), with a yield of 97.0%.

References:

CN111662247,2020,A Location in patent:Paragraph 0012; 0027-0030